Such cameras are already known. Due to the greater thickness of the sound-film tracked with the magnetic track, the cartridges of sound-film are larger than cartridges for silent-film. In principle, it is possible to insert a smaller silent-film cartridge into the larger compartment for the sound film cartridge. It is a disadvantage, however, that all the sound recording means, which normally are operated by the releaser and are, of course, important only for the tracked sound-film, are operated superfluously also with insertion of a silent-film cartridge. Thereby a higher wear on the sensitive sound recording parts results. Particularly, such wear appears at the surface of the pressure roll.